Circuit breaker disconnector



June 8, 1965 w. J. SCHULTZ 3,188,415

CIRCUIT BREAKER mscommcwon Filed April '25, 1962 3 Sheets-Sheet 1 June8, 1 965 v v. J. SCHULTZ 3,188,416

CIRCUIT BREAKER DISCONNECTOR Filed April 25, 1962 3 Sheets-Sheet 2 v %Jrroeucy Filed April 25, 1962 June 1965 w. J. SCHULTZ 3,188,416

CIRCUIT BREAKER DISGONNECTOR 3 Sheets-Sheet 3 United States PatentOfiice 3,188,416 CIRCUIT BREAKER DISCONNECTOR William J. Schultz,Yonkers, N.Y., assignor to Ward Leonard Electric (10., Mount Vernon,N.Y., a corporation of New York Filed Apr. 25, 1962, Ser. No. 196,143 3Claims. (Cl. 2tlt)51.09)

This invention relates to electrical apparatus for connecting separateloads to separate control devices by individual circuits, andparticularly to apparatus insuring that a circuit is open on the makingor breaking of; contact between a plug and receptacleconnecting aselected load to a selected control device.

The invention is directed particularly to the cold patching ofincandescent lamps to lighting control equipment, such as dimmers.However, the embodiments may be readily adapted for connecting othertypes of loads, such as motors, transformers, electric furnaces, platingequipment and the like, with or without interposing control equipment.

In stage li hting, the stage lights or spotlights are remotely mountedon batten strips above the stage or in various ways in the wings of thestage remotely from the control equipment. The control equipment maycomprise a large number of dimmers for individually controlling one ormore stage lights. The dimmers are connected to the stage lights throughpatch panels which permits a versatile connection of the dimmers to thestage lights so that any one dimmer may be connected to control any oneor more stage lights. The patch panel usually comprises a plurality ofelectrical receptacles and a plurality of plugs which are connected to arespective dimmer or stage light. The plugs and receptacles may passhigh currents, particularly when connections are made to unilluminatedfilament type lamps. The transference of high currents between the plugsand the receptacles should be avoided when a plug is being inserted orremoved. This may be accomplished by maintaining the circuit connectingthe dimmer and lamps open until the plug is fully seated in thereceptacle. This is known as cold patching since plug and receptacle arecold or deenergized when they come in mechanical contact, or breakcontact, with each other.

An object of this invention is to provide means to insure an opencircuit between control equipment and load on insertion or separation ofa plug in a plug and receptacle combination connecting the controlequipment and load.

Another object of the invention is to provide an inexpensive and readilyadaptable means for disruption of a circuit by a plug being insertedinto or removed from an electrical receptacle.

Other and further objects and advantages will be apparent from thefollowing description taken in connection with the drawings, in whichFIG. 1 illustrates a lighting circuit connecting stage lights to acontrol device through a patch panel with mechanical means actuating thetrip mechanism of the circuit breaker connected in the circuit;

FIG. 2 illustrates a lighting circuit connecting lamps to a controldevice through a patch panel with magnetic means for actuating the tripmechanism of the circuit breaker connected in the circuit;

FIG. 3 is a top View of the circuit breaker, a plug and a receptaclewith the receptacle partially illustrated in section;

FIG. 4 is a top view illustrating a plug, receptacle and circuit breakerwith a lever interposed between the plug and the circuit breaker;

FIG. 5 is a front perspective view of the circuit breaker;

3,188,416 Patented June 8, 1965 FIG. 6 is a perspective view of acircuit breaker with the casing in section to illustrate the operativemembers;

FIG. 7 is a fragmentary side view of the circuit breaker operativemembers with the contacts closed;

FIG. 8 is a side view of the circuit breaker operative members with thecontacts open;

FIG. 9 is a fragmentary perspective view of the trip mechanism of thecircuit breaker;

FTG. 10 is a side view of the plunger actuating the trip mechanism;

FIG. 11 is a side view of another embodiment of the plunger actuatinganother portion of the trip mechanism; and

FIG. 12 illustrates an embodiment of the plug and receptacle with aswitch for actuating the trip circuit breaker.

In describing the invention the specific embodiments illustrateincandescent lamps as the load and a variable voltage dimmer as thecontrol device or equipment. In F168. 1 and 2 the lamp loads 2i) areconnected to the dimmers 21 through the patch panels 22 in FIG. 1 and 23in FIG. 2.

The circuit is connected across input alternating current supplyterminals 24, 25. The patch panel 22 has a plug and receptacle assembly26 with the receptacle 27 mounted on the panel 28. The plug 29 isconnected in a conventional manner with the lamp load 20 by a flexiblecord 39. The receptacle 27 is connected through a circuit breaker 31 tothe control device or dimmer 21 and thence to terminal 24. The circuitbreaker 31 is mounted on the panel 28 adjacent to the receptacle 27 foractuation by the plug 29 in a manner later described herein.

The plug 29 is similar to conventional plugs and has a prong with ametal current carrying tip 32 and an insulating shaft 33 having an inneraxial conductor for connecting the tip 32 with the cable 36. A handle 34supports the insulating shaft 33 and the tip 32 and is used to insertthe plug into and remove it from the receptacle 27.

The receptacle 27 is of a conventional type with an insulating tubularholder 35 secured to the panel 28 by the nut 3% and collar 37. At thefree end the tubular holder 35 supports a metal conductive socket 38 andhas an opening 39 to receive the spring contacts 40 for engagement bythe tip 32. The terminal post 41 is located at the end of the holder 35for connecting the socket 38 to external leads 42 by means of the bolt43. The holder 35 has an opening 44 intermediate the ends thereof forreceiving a plunger 45 mounted on the circuit breaker 31. The plunger 45extends into the receptacle and is engaged by the tip 32 andsubsequently by the insulating shaft 33 for actuating the circuitbreaker 31. The plunger 45 on being moved into the circuit breaker 31opens the circuit breaker 31 to open the supply circuit. The insulatingshaft 33 has an intermediate circular groove 46 for recessing theplunger 45 after the tip 32 engages the contacts 46 so that the circuitbreaker may be turned on. The circuit breaker is illustrated in FIG. 5and has a casing 47 housing the operating components and a switch knob48 for manual actuation of the breaker. The breaker 31 is mounted on thepanel 28 so that the knob 48 projects through the panel on the same sideas the handle 34 of the plug for easy actuation.

In FIGS. 6 through 9 the operative portions of the circuit breaker areillustrated and are of a conventional type and are described herein forthe purpose of illustrating the adaptation to the present invention. Thecontact 50 is securely fastened in fixed relation to the casing 47 andthe movable contact 51 is pivotally mounted in the bracket 52 with thespring 53 also mounted on the bracket 52 and urging the contact 51 outof engagement with the contact 50. The knob 48 is pivotally mounted onthe bracket 54 and pivotally connected at 55 to the link 56 which is inturn pivotally connected to the link 57 which is pivotally connected tothe contact 51. The links 56 and 57 are held in a non-pivotal relationby the cam 58 and the catch 59. The catch 59 is pivotally mounted in thelink 57 and urged to rotate in a counter-' clockwise direction by ahelical spring 60. The catch 59 has a U shape with a leg 61 engaging thecam 58 and a leg 62 for engagement by the armature 63. The leg 61 has anotch 64 which on rotation of the catch 59 in a clockwise directiondisengages leg 61 from the cam 58 to permit relative pivotal movement ofthe links 56 and 57. Since the spring 53 is urging the contact 51 out ofengagement, the links 56 and 57 will break and then contact 51 snappedinto the position illustrated in FIG. 8. The armature 63 is biased bythe spring 65 out of contact with the catch 59 and the electromagnet 66.However, on passage of an overload current through the terminals 67,winding 68, braided connector 69, movable contact 51 and fiXed contact50 to the terminal 70, the armature will be drawn downward and rotatedto engage the leg 62 of the catch 59 into a position as illustrated inFIG. 9 permitting relative rotation of the links 56, 57. Thus the catch59, armature 63, electromagnet 66 and associated parts form the tripmechanism opening the circuit breaker.

In FIG. the plunger 45 has a conical tip 71 forming a trip means forengaging the catch 59 to rotate it in a similar manner to the armature63 for tripping the circuit breaker. A helical spring 72 engages acollar 73 secured to the plunger 45 to normally hold the plunger 45 outof contact with the catch 59 so that the circuit breaker will operate inits usual and normal manner. 0n insertion of the plug 29, the tip 32engages the plunger 45 and forces it inward to engage the catch 59 andholds the plunger 45 in the compressed position by the insulator 33 anduntil the plug is fully seated and the plunger 45 returns to its normalposition by the recess 44.

Thus during the insertion of the plug the circuit breaker contacts 50and 51 are separated so that no current can pass'between the tip 32 andthe socket 38.

Instead of the plunger 45 or trip means engaging the catch 59 it mayengage the armature 63, as illustrated in FIG. 11, and rotate thearmature on actuation of the plunger 45 with the armature 63 engagingthe catch 59 for opening the circuit breaker contacts. Instead ofmechanically actuating the circuit breaker, the circuit breaker may bemagnetically actuated, in addition to actuation by the winding 68, by acoil 74 on the electromagnet 66. The coil 74 is connected in parallel tothe plug and receptacle combination to conduct current from the supplyside of the load to the socket 38. A microswitch 75 actuated by a'plunger 76 is connected in series with the Winding 74. The microswitchis mounted on the panel 28 adjacent to the receptacle 27 and has aresilient arm 77 with a roller 78 fitting in the opening 44 in theinsulating holder 35 for engagement by the tip 32 and shaft 33 of theprong. The arm 77 actuates the plunger 76 to close the contacts in orderto supply current to the electromagnet 66. The winding 74 actuates thearmature 63 to trip the circuit breaker.

It is thus seen from the foregoing embodiments that the main circuit isopen on insertion of the plug 29 into the receptacle 27 so no arcing orsparking will occur between the tip 32 and the socket 38, and thuspitting or possible welding of these members together is avoided. Aspreviously stated the foregoing embodiments may be readily adapted forconnecting other types of electrical equipment without departing fromthe invention as set forth in the appended claims.

*I claim:

1. Electric apparatus for completing an electrical circuit whilemaintaining the circuit in open condition during completion ordisruption of the circuit comprising a prong having a conductive tip, areceptacle having a prong holder and a conductive socket for receivingsaid prong with said tip fitting in said socket for transferring currenttherebet-ween, electrical means having contacts in make or open relationin series with said socket and tip and having a trip mechanism foropening the contacts, trip means for actuating said trip mechanismindependent of the current through said contacts including movableprojecting means engageable by said prong to actuate said trip means andsaid prong having means for actuating said projecting means to rendersaid contacts in an open condition while said tip is forming anengagement With or disengagement from said socket.

2. Electrical apparatus for completing an electrical circuit whilemaintaining the circuit in open condition during completion ordisruption of the circuit comprising a plug having a prong with aconductive tip and a circumferential groove intermediate the length ofthe prong, a receptacle having a plug holder and a conductive socket forreceiving said prong with said tip fitting in said socket fortransferring current therebetween, said holder having an intermediateopening registering with said groove on seating of said tip in saidsocket, electrical means having contacts in make or open relation inseries with said socket and tip and having -a trip mechanism for openingthe contacts, and movable means for actuating said trip mechanism havinga plunger projecting into said opening in said holder for engagement bysaid prong to render said contacts in an open condition to preventtransfer of current while said tip is forming an engagement ordisengagement with said contact.

3. Electrical apparatus for completing an electrical circuit whilemaintaining the circuit in open condition during completion ordisruption of the circuit comprising a prong having a conductive tip, areceptacle having a prong holder and a conductive socket for receivingsaid prong with said tip fitting in said socket for transferring currenttherebetween, electrical means having contacts in make or open relationin series with said socket and tip and having a trip mechanism with anelectrom'agnet having a winding actuating said electromagnet on passingof excessive current for opening the contacts, trip means for actuatingsaid trip mechanism independent of the current through said contactsincluding a winding connected in parallel to said prong and receptacleto energize said electromagnet on passage of current to open thecontacts and including a switch in series with said second winding forconnecting said second winding to a current supply, said switch havingmovable projecting means engageable by said prong to actuate said switchand said prong having means for actuating said project-ing means torender said contacts in an open condition by energizing said secondwinding while said tip is forming an engagement or disengagement withsaid contact.

References Cited by the Examiner UNITED STATES PATENTS 1,731,417 10/29Hartwig 20050 BERNARD A. GILHEANY, Primary Examiner.

1. ELECTRIC APPARATUS FOR COMPLETING AN ELECTRICAL CIRCUIT WHILEMAINTAINING THE CIRCUIT IN OPEN CONDITION DURING COMPLETION ORDISRUPTION OF THE CIRCUIT COMPRISING A PRONG HAVING A CONDUCTIVE TIP, ARECEPTACLE HAVING A PRONG HOLDER AND A CONDUCTIVE SOCKET FOR RECEIVINGSAID PRONG WITH SAID TIP FITTING IN SAID SOCKET FOR TRANSFERRING CURRENTTHEREBETWEEN, ELECTRICL MEANS HAVING CONTACTS IN MAKE OR OPEN RELATIONIN SERIES WITH SAID SOCKET AND TIP AND HAVING A TRIP MECHANISM FOROPENING THE CONTACTS, TRIP MEANS FOR ACTUATING SAID TRIP MECHANISMINDEPENDENT OF THE CURRENT THROUGH SAID CONTACTS INCLUDING MOVABLEPROJECTING MEANS ENGAGEABLE BY SAID PRONG TO ACTUATE SAID TRIP MEANS ANDSAID PRONG HAVING MEANS FOR ACTUATING SAID PROJECTING MEANS TO RENDERSAID CONTACTS IN AN OPEN CONDITION WHILE SAID TIP IS FORMING ANENGAGEMENT WITH OR DISENGAGEMENT FROM SAID SOCKET.